In recent years, in a semiconductor device manufacturing process, semiconductor substrates such as a silicon wafer, a compound semiconductor wafer and the like become larger in diameter and thinner in thickness. A semiconductor substrate having a large diameter and a thin thickness may have a warp or a crack during a transfer operation or a grinding process. Thus, in the semiconductor device manufacturing process, the semiconductor substrate is reinforced by bonding a support substrate to the semiconductor substrate. Then, the reinforced semiconductor substrate is transferred or subjected to a grinding process and thereafter the support substrate is delaminated from the reinforced semiconductor substrate.
By way of example, a first holding unit may hold the semiconductor substrate while a second holding unit may hold the support substrate. The support substrate may be delaminated from the reinforced semiconductor substrate by vertically moving an outer peripheral portion of the second holding unit.
The delamination process for the semiconductor substrate and the support substrate may be finished after the semiconductor substrate and the support substrate are delaminated in the aforementioned manner and bonding surfaces of the semiconductor substrate and the support substrate are cleaned. However, the aforesaid delamination process does not consider the efficiency of the delamination processes.